Stackable chair assembly

ABSTRACT

A chair assembly adapted to be nested with a second chair assembly identical to the chair assembly. The chair assembly comprises a seating portion and a back support. The seating portion includes a top seat surface, a bottom seat surface generally parallel to the top seat surface, a first side seat edge, a second side seat edge, and a front edge. The back support is generally perpendicular to the seating portion and includes an inner back support surface, an outer back support surface generally parallel to the inner back support surface, a first side back support edge, a second side back support edge, and a top back support edge. A first return flange disposed on the first side back support edge of the back support and a second return flange disposed on the second side back support edge of the back support. A first recess can be disposed on the inner surface of the back support, and is adapted to receive a first return flange of a second chair assembly nested with the unitary shell. A second recess can be disposed on the inner surface of the back support and is adapted to receive a second return flange of the second chair assembly nested with the unitary shell.

TECHNICAL FIELD

The present invention generally relates to chairs, and morespecifically, to a stackable chair.

BACKGROUND

Chairs for extended seating applications, such as conference rooms andschool classrooms are preferably durable and comfortable. Often times,these chairs are stackable or nestable for storage and transportationpurposes. Typical stackable and/or nestable chairs are formed from agenerally L-shaped molded shell that is defined by a generallyhorizontal seat and a generally vertical back support and includes apair of inverted U-shaped leg members attached to the generally L-shapedshell.

A stackable chair is stacked by placing the inverted U-shaped legmembers of one chair on top of the leg members of another chair suchthat the seat of the upper chair is supported just above the seat of thelower chair. The rear surface of the back support of the upper chair canbe spaced apart from the front surface of the back support of the lowerchair. Alternatively, the rear surface of the back support of the upperchair can be rested against the front surface of the back support of thelower chair when in the stacked configuration.

Stackable chairs are generally formed of hard plastic, or other similarmaterial, and are designed to be rigid so that they can be properlystacked. However, these hard shells are uncomfortable to a user whenused in extended seating applications and are not aesthetically pleasingto consumers and users of the chairs. In an effort to improve comfortand create aesthetically pleasing design features, the shells can beergonomically designed and can include, among other things, anintentional flex between the seat and back support. However, while theergonomic design and intentional flex may improve design and comfort, itcreates instability when multiple chairs are stacked on top of eachother. Therefore, the rigid chairs fail to provide comfort while theflexible shells do not permit multiple chairs to be stacked safely. Thepresent invention is provided to solve these and other problems.

SUMMARY

The present invention relates to a chair assembly adapted to be nestedwith a second chair assembly identical to the chair assembly. The chairassembly comprises a seating portion and a back support. The seatingportion includes a top seat surface, a bottom seat surface generallyparallel to the top seat surface, a first side seat edge, a second sideseat edge, and a front edge. The back support is generally perpendicularto the seating portion and includes an inner back support surface, anouter back support surface generally parallel to the inner back supportsurface, a first side back support edge, a second side back supportedge, and a top back support edge. A first return flange is disposed onthe first side back support edge of the back support and a second returnflange is disposed on the second side back support edge of the backsupport.

A first recess can be disposed on the inner surface of the back support,and is adapted to receive a first return flange of a second chairassembly nested with the unitary shell. A second recess can be disposedon the inner surface of the back support and is adapted to receive asecond return flange of the second chair assembly nested with theunitary shell.

The chair assembly may further comprise a first inverted U-shaped legmember secured to the outer surface of the generally horizontal seatingsurface and a second inverted U-shaped leg member, secured to the outersurface of the generally horizontal seating surface.

When the second chair assembly is nested with the chair assembly, thefirst inverted U-shaped leg member of the second chair assembly isnested with the first inverted U-shaped leg member of the chair assemblyand the second inverted U-shaped leg member of the second chair assemblyis nested with the second inverted U-shaped leg member of the chairassembly.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective front view of a stackable chair assembly inaccordance with an embodiment of the present invention;

FIG. 2 is a perspective rear view of a stackable chair assembly inaccordance with an embodiment of the present invention;

FIG. 3 is a front view of a stackable chair assembly in accordance withan embodiment of the present invention;

FIG. 4 is a rear view of a stackable chair assembly in accordance withan embodiment of the present invention;

FIG. 5 is a side view of a stackable chair assembly in accordance withan embodiment of the present invention;

FIG. 6 is a top view of a stackable chair assembly in accordance with anembodiment of the present invention;

FIG. 7 is a bottom view of a stackable chair assembly in accordance withan embodiment of the present invention;

FIG. 8 is perspective front view of a second stackable chair assemblystacked on top of a first stackable chair assembly in accordance with anembodiment of the present invention;

FIG. 9 is a perspective rear view of the embodiment of the presentinvention shown in FIG. 8; and,

FIG. 10 is a side view of the embodiment of the present invention shownin FIG. 8.

DETAILED DESCRIPTION

While the present invention is susceptible to embodiments in manydifferent forms, there is shown in the drawings and will herein bedescribed an example of the invention with the understanding that thepresent disclosure is to be considered as an exemplification of theprinciples of the invention and is not intended to limit the broadaspects of the invention to the examples illustrated.

FIG. 1 is a perspective front view of a stackable chair assembly 10 inaccordance with one embodiment of the present invention. In one example,the stackable chair assembly 10 is formed from a generally L-shapedone-piece molded shell 11 and a pair of inverted U-shaped leg members13, 15 secured to the L-shaped molded shell 11 by suitable means.

The shell 11 is preferably formed from an integral piece of resilientmaterial, such as a polymeric material, and is molded to include agenerally horizontal seating portion 17 and a generally vertical backsupport 19. The shell 11 may also be constructed of other materials suchas wood, steel, or such other material known to those of ordinary skillin the art. The seating portion 17 and back support 19 have respectiveinner surfaces 23, 49 defining a seating surface 20 against which theuser is seated. The seating area 20 has a generally concave contour tofacilitate engagement with the body of a user seated thereon.

Preferably, the shell 11 is molded to combine the features of rigid andflexible chairs and ensure comfort, performance, and durability. In thatmanner, the contour of the shell 11 may be manufactured to include anintentional flex between the seating portion 17 and the back support 19such that the back support 19 flexes rearwardly with respect to theseating portion 17 when it is leaned against by a user. Further, inorder to assist balancing structural rigidity with the comfort offlexibility, the shell 11 may include a tall return flange 21 disposedaround the perimeter of the shell 11 to ensure the angle between theseating portion 17 and back support 19 will not open far enough to causefailure and/or cause permanent damage to the chair. This allows thestackable chair assembly 10 to be used in a range of postures,including, for example, sitting at a work surface and reclining in alecture posture.

As shown in FIGS. 1-7, the seating portion 17 includes a top surface 23,a bottom surface 25, a front edge 27, a first side edge 29, and a secondside edge 31. The top surface 23 forms a portion of the seating area 20.The seating portion 17 may be in a generally horizontal plane, however,it is contemplated that the seating portion 17 may also be slightlytilted rearward or forward.

As discussed above, a return flange 21 is disposed on the first sideedge 29, the front edge 27, and the second side edge 31. The returnflange 21 around the edges of the seating portion 17 is generallyvertical and perpendicular to the top surface 23 of the seating portion17. In one example, the first side edge 29, the front edge 27, and thesecond side edge 31 are molded to form the return flange 21. Typically,the area where the seating portion 17 intersects with the back support19, also known as the hip area 33, is the area of highest stress when auser is sitting in the chair 11. Therefore, in order assist withstructural integrity, the return flange 21 may be formed such that it ishas the highest height at the hip area 33 and transitions to asubstantially lower height near the front edge 27. In addition, theseating portion 17 may transition from the generally horizontal topsurface 23 to the generally vertical return flanges 21 on the peripheryof the seating portion.

As shown in FIG. 2, a plurality of support ribs 35 can be disposed onthe bottom surface 25 of the seating portion 17. The support ribs 35 arepositioned substantially near the front edge 27 of the seating portion17 and provide additional support for the curvature of the front edge27. In addition, a plurality of bottom ribs 37 traverse the bottomsurface 25 of the seating portion 17 between the front edge 27 and thehip portion 33. The bottom ribs 37 provide additional support when auser is sitting in the chair assembly 10. As will be described herein,the bottom ribs 37 include a C-shaped cut out section 73 for acceptingthe inverted U-shaped leg members 13, 15.

As described above, the chair assembly 10 is molded to include a backsupport 19 that flexes rearwardly with respect to the seating portion 17when it is leaned against by a user. As illustrated in FIGS. 1-6, theback support 19 includes an inner surface 49, an outer surface 51, a topedge 43, a first side edge 45, and a second side edge 47. The innersurface 49 forms the generally vertical portion of the seating area 20.The back support 19 may be in a generally vertical plane, however, it iscontemplated that the back support 19 may also be slightly tiltedrearward or forward. The back support 19 includes a thoracic support 41and a lumbar region 39. In one example, the thoracic support 41 is widerthan the lumbar region 39 and the back support 19 tapers from the topedge 43 towards the hip area 33.

The return flange 21 is disposed on the top edge 43, the first side edge45, and the second side edge 47 of the back support 19. The returnflange 21 around the edges of the back support 19 is generallyperpendicular to the inner surface 49 of the back support 19. In oneexample, the back support 19 transitions from the generally verticalback support 19 to the generally perpendicular return flange 21 on theperiphery of the back support 19. As with the seating portion 17, thereturn flange 21 can be taller in the hip area 33 and can transition toa substantially lower height near the top edge 43. In addition, as withthe return flange 21 disposed on the seating portion, 17, the top edge43, the first side edge 45, and the second side edge 47 may be molded toform the return flange 21.

As shown in FIG. 2 and FIG. 4, a plurality of spaced apart longitudinalribs 53 may be disposed on the outer surface 51 proximate the hip area33 of the chair assembly 10. Preferably, the outer surface 51 includes15 longitudinal ribs 53 which are spaced apart approximately 1½ inchesfrom each other, however any suitable spacing distance may be used. Theouter surface 51 of the seating portion 17 may be molded to formlongitudinal ribs 53. The longitudinal ribs 53 traverse the chairassembly 10 from the bottom surface 25 of the seating portion 17 to theouter surface 51 of the back support 19. The longitudinal ribs 53 mayend at different heights on the outer surface 51 of the back support 19.

A cross bow rib 55 may be disposed on the outer surface 51 of the backsupport 19 and cross-sectionally traverses the plurality of longitudinalribs 53 on the outer surface 51 of the back support 19. The outersurface 51 of the back support 19 may be molded to form the cross bowrib 55, or the cross bow rib 55 may be attached by suitable means, asknown to those of ordinary skill in the art. The cross bow rib 55 may bea U-shape rib with one end being substantially near the first side edge45 and the other end being substantially near the second side edge 47.Although a single cross bow rib 55 is shown, any number of cross bowribs 55 may be used. Along with the return flange 21, the longitudinalribs 53 and the cross bow rib 55 assist in balancing the structuralrigidity, while still providing the intentional flex between the seatingportion 17 and the back support 19.

The inner surface 49 of the back support 19 may include a concavestacking recess 63, as shown in FIG. 1 and FIG. 3. When the chairassembly 10 is viewed from the back side, the stacking recess 63 appearsas a convex protrusion on the outer surface 51 of the back support 19.Preferably, the outer surface 51 is molded to form the stacking recess63. The stacking recess 63 may be a closed recess pocket contour in theback support 19 surface and is shaped to accept and mate with the returnflange 21 of a second chair assembly 100 stacked on top of the chairassembly 10. Alternatively, the stacking recess 63 may include anaperture such that a rope, or other securing means, can be fed throughto secure the chair to a pallet. The two stacking recesses 63, incombination with return flanges 21 from a second chair assembly 100stacked on top, creates two points of contact. When multiple chairassemblies 10 are stacked on top of one another, the combination of thestacking recess 63 of the chair below and the return flange 21 of thechair above laterally stabilizes a stack of multiple chair assemblies.The longitudinal ribs 53 and the cross bow rib 55 described above assistin increasing the shell strength of the chair assembly 10 in the areasof the stacking recesses 63.

FIGS. 8-10 illustrates a second chair assembly 100 stacked on top of thebottom chair assembly 10. The second chair assembly 100 is identical tothe first chair assembly 10. When the second chair assembly 100 isplaced on top of the bottom chair assembly, the return flanges 121 onthe first side edge 145 and the second side edge 147 of the second chairassembly 100 are received and nested in the stacking recesses 63 of thebottom chair assembly 10.

The back support 19 may also include a hand hole 57 to provideassistance when the chair assembly 10 is lifted. The hand hole 57 is ofa generally oval shape and includes a lip 59 around the periphery of thehand hole 57. A company name, or other such logo or indicia, may also beincluded on the chair assembly 10. For example, the name of themanufacturer 61 of the chair assembly 10 may be molded on the backsupport 19 above the hand hole 57.

As shown in FIG. 1-7, the chair assembly 10 includes legs 67, 69, 75, 79secured to bottom surface 25 of the shell 11. In one example, a U-shapedback leg member 13 and a U-shaped front leg member 15 are secured to thebottom surface 25 of the seating portion 17 of the chair assembly 10. Asdiscussed above, the bottom ribs 37 may include a C-shaped cut-out 73 toaccept the back leg member 13 and the front leg member 15. Typically,the leg members 13, 15 are secured to the bottom surface 25 by a screw,however, any means known to those of ordinary skill in the art may beused.

The back leg member 13 may include a first leg 67 and a second leg 69that is separated from the first leg 67 by a generally horizontal member65. The lower ends of the first leg 67 and the second leg 69 may includecontacting ends 71 that contact the floor, or other such surfaces. Thegenerally horizontal member 65 extends between and interconnects theupper portions of the first leg 67 and the second leg 69. The back legmember 13 may be a continuous piece of tubing which is bent into thegenerally inverted U-shaped member. In addition, the first leg 67 andthe second leg 69 of the back leg member 13 may be at an outward anglerelative to the vertical back support 19.

Similar to the back leg member 13, the front leg member 15 may include afirst leg 75 and a second leg 79 that is separated from the first leg 75by a generally horizontal member 77. The lower ends of the first leg 75and the second leg 79 may also include contacting ends 71 that contactthe floor, or other such surfaces. The generally horizontal member 77extends between and interconnects the upper portions of the first leg 75and the second leg 79. As with the back leg member 13, the front legmember 15 may be continuous piece of tubing which is bent into thegenerally inverted U-shaped member. In addition, the first leg 75 andthe second leg 79 of the front leg member 15 may be at an anglegenerally perpendicular to the bottom surface 25 of the seating portion17.

With reference again to FIGS. 8-10, a second chair assembly 100 isstacked on top of a first chair assembly 10. When the second chairassembly 100 is placed on top of the bottom chair assembly 10, the frontleg members 115 of the second chair assembly 100 nest on top of thefront leg members 15 of the bottom chair assembly 10. Preferably, anintentional clearance 81 is created between the front leg members 115 ofthe second chair assembly 100 and the front leg members 15 of the bottomchair assembly 10. The intentional clearance may be ½ inches, howeverany other suitable clearance may be used. Specifically, the first leg167 of the second chair assembly 100 is nested on the first leg 67 ofthe bottom chair assembly 10 and the second leg 169 of the second chairassembly 100 is nested on the second leg 69 of the bottom chair assembly10. The stacking configuration creates two points of contact on thefront leg member 15.

Similarly, the back leg member 113 of the second chair assembly 100 neston top of the back leg member 13 of the chair assembly 10 when thesecond chair assembly 100 is placed on top of the chair assembly 10.Specifically, the first leg 175 of the second chair assembly 100 isnested on the first leg 75 of the bottom chair assembly 10 and thesecond leg 179 of the second chair assembly 100 is nested on the secondleg 79 of the bottom chair assembly 10. The stacking configurationcreates two points of contact on the back leg member 13.

The two stacking recesses 63, the back leg members 13, and the front legmembers 15 allow the chair assembly 10 to stack with six points ofcontact without distorting the shell 11. Each point of contact improvesstack stability and allows for safer transportation and storage ofchairs. This configuration can allow for chair assemblies 10 to bestacked and bundled in a safe manner. This further allows more chairassemblies 10 to be placed and transported on a trailer, or othersimilar storage container, thereby resulting in cost and space savings.

While the foregoing has described what is considered to be the best modeand/or other examples, it is understood that various modifications maybe made therein and that the subject matter disclosed herein may beimplemented in various forms and examples, and that they may be appliedin numerous other applications, combinations and environments, only someof which have been described herein. Those of ordinary skill in that artwill recognize that the disclosed aspects may be altered or amendedwithout departing from the true spirit and scope of the subject matter.Therefore, the subject matter is not limited to the specific details,exhibits and illustrated examples in this description. It is intended toprotect any and all modifications and variations that fall within thetrue scope of the advantageous concepts disclosed herein.

1. A chair assembly adapted to be nested with a second chair assembly,the chair assembly comprising: a seating portion having a top seatsurface, a bottom seat surface generally parallel to the top seatsurface, a first side seat edge, a second side seat edge, and a frontedge; a back support generally perpendicular to the seating portion, theback support having an inner back support surface, an outer back supportsurface generally parallel to the inner back support surface, a firstside back support edge, a second side back support edge, and a top backsupport edge; a first return flange disposed on the first side backsupport edge of the back support; a second return flange disposed on thesecond side back support edge of the back support; a first recessdisposed on the inner back support surface of the back support, thefirst recess adapted to receive a first return flange of a second chairassembly nested with the chair assembly; and, a second recess disposedon the inner back support surface of the back support, the second recessadapted to receive a second return flange of the second chair assemblynested with the chair assembly.
 2. The chair assembly of claim 1 whereinthe seating portion is in a generally horizontal plane and the backsupport is in a generally vertical plane and the seating portion andback support define a unitary shell that transitions from the generallyhorizontal seating portion to the generally vertical back support. 3.The chair assembly of claim 1 wherein the first return flange and thesecond return flange are generally outwardly perpendicular to the innersurface of the back support.
 4. The chair assembly of claim 1 whereinthe first side back support edge is molded to form the first returnflange and the second side back support edge is molded to form thesecond return flange.
 5. The chair assembly of claim 1 furthercomprising a plurality of support ribs disposed on the bottom seatsurface of the seating portion.
 6. The chair assembly of claim 1 furthercomprising a plurality of longitudinal ribs disposed on the outersurface of the back support.
 7. The chair assembly of claim 1 furthercomprising a cross bow rib disposed on the outer surface of the backsupport.
 8. The chair assembly of claim 1 wherein the back supportfurther includes a top portion and a bottom portion wherein the backsupport tapers from the top portion of the back support to the bottomportion of the back support.
 9. The chair assembly of claim 1 furthercomprising a plurality of legs.
 10. The chair assembly of claim 9wherein when the second chair assembly is nested with the chairassembly, the plurality of legs of the second chair assembly nest withthe respective plurality of legs on the chair assembly.
 11. The chairassembly of claim 1 further comprising a first inverted U-shaped legmember and a second inverted U-shaped leg member, wherein each legmember is secured to the bottom surface of the seating portion.
 12. Thechair assembly of claim 11 wherein when the second chair assembly isnested with the chair assembly, the first inverted U-shaped leg memberof the second chair assembly is nested with the first inverted U-shapedleg member of the chair assembly and the second inverted U-shaped legmember of the second chair assembly is nested with the second invertedU-shaped leg member of the chair assembly.
 13. The chair assembly ofclaim 1 wherein the back support further comprises a hand hole.
 14. Achair assembly adapted to be nested with a second chair assembly, thechair assembly comprising: a seating portion having a top seat surface,a bottom seat surface parallel to the top seat surface, a first sideseat edge, a second side seat edge, and a front edge; a back supporthaving an inner back support surface, an outer back support surfaceparallel to the inner back support surface, a first side back supportedge, a second side back support edge, and a top back support edge; afirst return flange disposed on the first side back support edge of theback support; a second return flange disposed on the second side backsupport edge of the back support; a first recess disposed on the innerback support surface of the back support, the first recess adapted toreceive a first return flange of a second chair assembly nested with theshell; a second recess disposed on the inner back support surface of theback support, the second recess adapted to receive a second returnflange of the second chair assembly; and, a plurality of legs secured tothe bottom seat surface of the seating surface wherein when the secondchair assembly is nested with the chair assembly, a portion of the legsof the second chair assembly abuts a portion of the respective legs ofthe chair assembly.
 15. The chair assembly of claim 14 wherein theplurality of legs comprises a first leg and a second leg, a third legmember and a fourth leg wherein when the second chair assembly is nestedwith the chair assembly, a portion of the first leg of the second chairassembly abuts a portion of the first leg of the chair assembly, aportion of the second leg of the second chair assembly abuts a portionof the second leg of the chair assembly, a portion of the third leg ofthe second chair assembly abuts a portion of the third leg of the chairassembly, and a portion of the fourth leg of the second chair assemblyabuts a portion of the fourth leg of the chair assembly.
 16. The chairassembly of claim 14 further comprising a first inverted U-shaped legmember and a second inverted U-shaped leg member, wherein each legmember is secured to the bottom surface of the seating portion and thefirst inverted U-shaped leg member includes a first leg and a second legand the second inverted U-shaped leg member includes a third leg and afourth leg.
 17. The chair assembly of claim 16 wherein when the secondchair assembly is nested with the chair assembly, the first invertedU-shaped leg member of the second chair assembly is nested with thefirst inverted U-shaped leg member of the chair assembly and a portionof the first inverted U-shaped leg member of the second chair assemblyabuts a portion of the first inverted U-shaped leg member of the chairassembly further wherein the second inverted U-shaped leg member of thesecond chair assembly is nested with the second inverted U-shaped legmember of the chair assembly and a portion of the second invertedU-shaped leg member of the second chair assembly abuts a portion of thesecond inverted U-shaped leg member of the chair assembly.
 18. The chairassembly of claim 14 wherein the seating portion is in a generallyhorizontal plane and the back support is in a generally vertical planeand the seating portion and back support define a unitary shell thattransitions from the generally horizontal seating portion to thegenerally vertical back support.
 19. The chair assembly of claim 14wherein the first return flange and the second return flange aregenerally outwardly perpendicular to the inner surface of the backsupport.
 20. The chair assembly of claim 14 wherein the first side backsupport edge is molded to form the first return flange and the secondside back support edge is molded to form the second return flange. 21.The chair assembly of claim 14 further comprising a plurality of supportribs disposed on the bottom seat surface of the seating portion.
 22. Thechair assembly of claim 14 further comprising a plurality oflongitudinal ribs disposed on the outer surface of the back support. 23.The chair assembly of claim 14 further comprising a cross bow ribdisposed on the outer surface of the back support.
 24. The chairassembly of claim 14 wherein the back support further includes a topportion and a bottom portion wherein the back support tapers from thetop portion of the back support to the bottom portion of the backsupport.
 25. The chair assembly of claim 14 wherein the back supportfurther comprises a hand hole.
 26. A stackable chair configurationhaving a first chair assembly nested with a second chair assembly, thestackable chair configuration comprising: a first chair assemblycomprising: a seating portion having a top seat surface, a bottom seatsurface parallel to the top seat surface, a first side seat edge, asecond side seat edge, and a front edge; a back support having an innerback support surface, an outer back support surface parallel to theinner back support surface, a first side back support edge, a secondside back support edge, and a top back support edge; a first returnflange disposed on the first side back support edge of the back support;a second return flange disposed on the second side back support edge ofthe back support; a first recess disposed on the inner back supportsurface of the back support; a second recess disposed on the inner backsupport surface of the back support; and, a plurality of legs secured tothe bottom seat surface of the seating surface; a second chair assemblynested on top of the first chair assembly, the second chair assemblycomprising: a seating portion having a top seat surface, a bottom seatsurface parallel to the top seat surface, a first side seat edge, asecond side seat edge, and a front edge; a back support having an innerback support surface, an outer back support surface parallel to theinner back support surface, a first side back support edge, a secondside back support edge, and a top back support edge; a first returnflange disposed on the first side back support edge of the back supportwherein the first return flange nests with the first recess disposed onthe first side back support edge of the back support on the first chairassembly; a second return flange disposed on the second side backsupport edge of the back support wherein the second return flange nestswith the second recess disposed on the second side back support edge ofthe back support on the first chair assembly; a first recess disposed onthe inner back support surface of the back support; a second recessdisposed on the inner back support surface of the back support; and, aplurality of legs secured to the bottom seat surface of the seatingsurface wherein the legs of the second chair assembly nest with therespective plurality of legs on the first chair assembly
 27. Thestackable chair configuration of claim 26 wherein the plurality of legson the first chair assembly comprises a first leg and a second leg, athird leg member and a fourth leg and the second chair assemblycomprises a first leg and a second leg, a third leg member and a fourthleg wherein a portion of the first leg of the second chair assemblyabuts a portion of the first leg of the chair assembly, a portion of thesecond leg of the second chair assembly abuts a portion of the secondleg of the chair assembly, a portion of the third leg of the secondchair assembly abuts a portion of the third leg of the chair assembly,and a portion of the fourth leg of the second chair assembly abuts aportion of the fourth leg of the chair assembly.